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If the parameters URL_RETURN_OK and URL_RETURN_NO are not sent in the authorization request, then URL_RETURN parameter value is used for a customer's automatic redirection. If this parameter is also not sent, then the return URL_RETURN_OK and URL specified in "Merchants settings" section in Personal account are used.
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When customer returns to the merchant site the value of the order number is always transmitted as URL-encoded string: all non alpha-numeric characters (except '-' and '_'.) are replaced by the percent sign '%' followed by two digits hex code; spaces are replaced by '+' sign. This is important when the order number contains characters of non latin alphabet or some special symbols. |